With this precedent, as I read it, anyone who owns a residential parcel of at least 4600 square feet in an R-2A district (which includes much of South Berkeley) could demolish the existing house and build three two-story houses. So long as the required setbacks and so on were met, state law would require the city to approve it.
Similarly, anyone who owns a parcel on a lot of at least 4500 square feet in an R-2 district (which includes most of the rest of South Berkeley) could demolish the existing house and build two two-story houses. Or just add a second house, if the yard is big enough.